The answer is -7m, but I don’t know how that’s the answer. Can anyone explain?

Explanation:
At first it is in 14m position but position doesn't matter in displacement, similar case for time taken.
So at first it travels 6m in positive direction.
So displacement= 6m
Then it travels 13 in opposite or negative direction.
So displacement = 6 -13 m = -7 m
Hope it helps ya
You're standing in the lobby of a huge building.
You go up 6 floors.
You stop and catch your breath.
You go down 13 floors.
Where do you end up ?